No personal experience, but what I’ve read is that they are fine for getting a quick and relative reading. Is it very alkaline, alkaline, neutral, etc. But they aren’t exact enough to determine how to amend. For that, my understanding is that you need an exact reading because for calculating lime, the Ph has to be basically to the decimal point because there’s a big difference with every .1 you need to move it.
I went the next step up and bought a test kit. More expensive, bigger mess, and you need distilled water to do the tests, but at least I can do as many as I want with reasonable accuracy.
It’s probably worth noting too that it takes quite a big of time alter the Ph. The farm next to my property has an alfalfa field and they’ve been trying to move the Ph by spreading ag lime for the past 3 years. They are just now getting close to their target Ph after 3 years such that they will probably be there next year. I’m not sure how many tons they put on that 40 acres, but just this year it’s one heck of a pile that got spread out on that field.
Grouse